The Effect of Decreasing the Dosage of Cyclosporine A 0.05% on Dry Eye Disease After 1 Year of Twice-Daily Therapy

Purpose: To evaluate the effect of decreasing topical cyclosporine 0.05% (tCSA) (Restasis; Allergan, Irvine, CA) from twice-daily dosing to once-daily dosing in patients who have already completed 12 months of twice-daily therapy for dry eye disease. Design: Prospective, randomized, single-masked, parallel group comparison. Participants: One hundred patients who had already been treated with tCSA twice daily for more than 1 year were randomized either to continue tCSA twice daily (n = 50) or to decrease tCSA once daily (n = 50). Methods: Clinical measurement of dry eye variables was performed for all patients at baseline, 3 months, and 6 months. Mean data were used for within-group (longitudinal analysis) and between-group comparisons (once daily vs. twice daily). Main Outcome Measures: Fluorescein tear break-up time, corneal fluorescein staining score, lissamine green staining score, Schirmer tear test, and ocular surface disease index. Results: At the end of the study, patients whose treatment dose was decreased to once daily demonstrated statistically significant improvement in tear break-up time [4.13 seconds (n = 37) vs. 3.11 seconds at baseline (n = 50); P = 0.0003] and lissamine green staining score [4.42 (n = 37) vs. 6.51 at baseline (n = 50); P = 0.024]; fluorescein staining score, Schirmer test results, and ocular surface disease index did not change significantly (P. 0.05). Furthermore, the once-daily group demonstrated significantly superior ocular surface disease index compared with the twice daily group [15.91 (n = 37) vs. 22.62 (n = 48); P = 0.0496]. The remaining outcome measures between once daily and twice daily were not significantly different (P > 0.05). Seven of 50 patients (14%) in the once-daily group (vs. 0% in the twice-daily group) ended the study early because of worsening dry eye symptoms (P < 0.05) and went back to twice-daily dosing. Conclusions: For patients with dry eye that has been controlled with tCSA twice daily for at least 1 year, decreasing to tCSA once daily may still allow suppression of the dry eye disease.